Question: Which is the presidential system for Joko Widodo in the head of government?
Paraphrase: What is the presidential system in the head of government for Joko Widodo?
SPARQL (Wikidata):  select distinct ?sbj where { ?sbj wdt:P6 wd:Q3318231 . ?sbj wdt:P31 wd:Q49892 } 
Answer: Indonesia